Process for feeding subdivided solids into an inclosed reaction mixture



Feb. 9, 1932. 1 .1. F. WAIT ET AL 1,844,195 a PROCESS FOR FEEDING SUBDIVIDED SOLIDS INTO v AN INCLOSED REACTION MIXTURE Filed Jan. 17. 1925 2 Sheets-Sheet l Feb. 9, 1932. J w ET L 1,844,195

PROCESS FOR FEEDING SUBDIVIDED SOLIDS INTO AN INCLOSED REACTION MIXTURE Filed Jan. 17, 1925 2 Sheets-Sheet 2 r M (g; INVENTORS ATTORNEY .l atented Feb. 9, 1932 UNITED STATES earner orrics JUSTIN E. WAIT, OF NEW YORK, AND CROSBY FIELD, BROOKLYN, NEW YORK, AS-

SIGNORS TO NATIONAL ANILINE & CHEMICAL 00., INCL, A CORPORATION .OF NEW YORK PROCESS FOR FEEDING SUBDIVIDED SOLIDS INTO AN INCLOSED REACTION MIXTURE Application filed January 17, 1925. Serial No. 3,096.

the intensity of the reaction that is to be promoted; and still more particularly to such a process in which the metal may be passed through a liquid seal and then into the reduction vessel above the surface of the reaction mixture. The invention will be un derstood from the description in connection with the accompanying drawings, in which Fig. 1 is an elevation partly in section; Fig. 2 is a view showing one of thedetails Fig. 31s a sectionalong the line a.a of Fig. 2; and r V Fig. 4 is an elevation in section of a modiiication. i In the drawings reference character 1 represents a feed hopper into which the material to be fed may be introduced, preferably in a dry condition. This hopper may be provided with astirrer driven in any convenient manner as, for example, by the gears 2, the

stirrer comprising a shaft 3 to which arms 1 are attached. These arms 1 are shaped so that their front edges are sharpened as shown more clearly at 5 in Fig. 3 having a sloping upper side and being so positioned that there '35 1s a rake behind the cutting edge in order to obviate thetendency for the material to become packed by these arms being turned. The ends of the arms 4: may be provided with scrapers 6 as more clearly shown in Fig. 2

which are likewise beveled on their front edges and'are provided with a rake or slight slope away from the plane of revolution of the cutting edge so as to throw thematerial away from the inner surface or restraining wall of the hopper and prevent its becoming packed. The walls of the hopper 1 converge at their lower portions and merge into a neck portion 7 The shaft 3 carries a feed control 8 in the neck portion 7 which serves to regu- 56 late the rate at which the material is fed through this neck portion. The neck portion 7 leads to a casing or conduit 9 in which casing conveyor 10 is located. This conveyor may be mounted on the shaft 11 which is driven by means of the gears 12. The casing 9 is closed at its respective ends by cover plates 13 and 14, the cover plate 13 serving as a stuffing box and bearing for the shaft 11 while cover plate 14i likewise serves as a bearing for the shaft. The casing 9 is also provided with an opening 15 with a cover thereon which opening may serve as a cleanout. An inlet forliquid may be provided at any convenient place leading either into the hopper 1 or the casing 9. Such an inlet is shown at 16 leading into the casing 9 near the neck portion 7. r

The casing 9 may be located either horizontally or at an angle to the horizontal and is connected to the vessel 17 Such connection may be made either to the cover 18 of the vessel or on the side thereof above or below the liquid level within the vessel. The vessel 17 may be provided with a stirring mechanism 19 driven by shaft 20 which shaft passes through a stuffing box 21 in the cover 18 and may be driven from any convenient source. p

In the modification shown in Fig. 4 the arrangement of the elements is in general similar to that just described and the elements are indicatedby the same reference characters. in this figurea vapor outlet pipe 22 leads from the reaction vessel 17 to a condenser 23 where-the vapors'are condensed and pass through the pipe 2 1 back into the casing 9, component of the reactionmixture itself thus being used to wet the incoming subdivided metallic mass. 'This figure also shows the gears 2 and 12 driven from a common source and interconnected so as to maintain the same relative speeds at all times.

The operation is as follows .Disintegrated non-liquid materials such as iron filings in a dry condition, for example,are introduced into the hopper 1 and the rate of speed of the gears 2 is regulated so as to cause the desired quantity of this'material to pass through the neck portion 7 into the casing 9 per unit of time. The drive mechanisms 2 and 12 are liquid.

preferably driven from the same source so as to have a predetermined relative speed with respect to each other and the feed control 8 and conveyor 10 are so proportioned that the conveyor 10 will always be capable of positively carrying the material into the vessel 17 more rapidly than it is fed into the casing 9. By making t 1e capacity of the conveying or transferring mechanism 9, 1O, 11 greater than the feeding capacity of the neck portion 7, plugging or stoppage of the casing 9 is avoided. Liquid may be fed into the subdivided metallic mass so as to wet the same through the inlet pipe 16, the rate of introduction of the liquid being whatever is desired, preferably sufficient to thoroughly wet the mass. The conveying mechanism 10 in the casing 9 should be of such a size or so arranged that the liquid can pass there through regardless of the quantity of solid material being transferred through the casing 9. If the conveyor 10 is of the ribbon type, its diameter should be appreciably less than the inside diameter of the casing 9 so as to leave a space for free passage of the The mixture of iron filings and liquid, for example, water passes from the casing 9 into the reaction vessel 17 where chemical reaction takes place. This sort of reaction may, for example, be the reduction of nitrobenzene to form aniline, or the reduction of nitro-toluene to form toluidine, or the reduction of alpha-nitro-naphthalene to form alpha-naphthylamine. If the chemical reactionis of such a character that vapors are evolved which should not be permitted. to escape, the casing 9 may be mounted so that the end next to the neck portion 7 is in a lower plane than the other end so that-the liquid passing therethrough will form a trap to prevent escape ofthe gases. The liquid in the casing serves to form a seal or trap for this purpose. Likewise when it is desired to operate the chemical reactions in the vessel 17 under vacuum, the liquid in the casing 9 serves a similar purpose. The static head provided by the slope of the casing 9 should be at least sufiicient to prevent escape of gases or breaking of the vacuum as the case may be. The actual available seal might be in excess of the static head due to the condensing effect of the cold liquid and solid constituents in the feed mechanism on the vapors issuing from the vessel 17. The feed of the subdivided metallic mass is preferably carried out continuously and at a rate dependent upon the intensity of the reaction within the vessel 17. Variation in the rate of feed is made to conform witn the intensity of the reaction and may even be stopped for short intervals, but in general the reaction cycle will consist of successive continuous operating periods.

In those reactions where the quantity of organic product being reacted upon influences the intensity of reaction, the control may be extended to variation in rate of feed of both the iron borings or other subdivided metal and the organic body. In other instances the control may be limited to the rate of addition of the organic body alone, the subdivided metal being fed at nearly uniform rate throughout the reaction. With this type of control it is often desirable to maintain an excess of the subdivided metal within the reaction zone while adding the organic body, the excess being measured with respect to that required to act upon the organic body present therein.

o claim:

1. The process of feeding solid or semisolid material into an inclosed reaction mixture which comprises forming a liquid seal, and passing the material through the liquid seal into the reaction mixture with a portion of the liquid from said'seal.

2. The process of feeding solid or semisolid material into an inclosed reaction mixture which comprises forming a liquid seal, passing the material'through said liquid'seal,

concurrently flowing the liquid and material and dropping said liquid and said material into the reaction mixture.

3. The process of feeding solid or semisolid material into an inclosed reaction mixture, whichcomprises forming a liquid seal, flowing the liquid from said liquid seal into the reaction mixture, passing the material concurrently through said liquid seal, and

theninto the. reaction'mixture, said liquid comprising one of the ingredients of the reaction mixture.

4. The process of feeding solid or semisolid material into an inclosed reaction-mixture, which comprises forming a body of liquid, sealing said body of liquid with a liquid seal, flowing the liquid from said seal into the reaction mixture; passing the material concurrently through said liquid seal,and then dropping the material into the reaction mixture, said liquid comprising one of the ingredients of the reaction mixture.

5. The process of feeding solid or semisolid material into an inclosed reaction mixture, which comprises volatilizing a portion of the reaction mixture, condensing the vapor evolved, forming a liquid seal with the condensate, flowing the condensate into the reaction mixture, and passing the material concurrently through said liquid seal and into the reaction mixture.

6. The process of feeding solid or semisolid material into an inclosed reaction mixture, which comprises volatilizing a portion of the reaction mixture, condensing the vapor evolved, forming a liquid seal with the condensate, flowing the condensate from the liquid seal into the reaction mixture, and passing the material concurrently through said liquid and into the reaction mixture from a point above the level of the reaction mixture.

7. The process of reducing an aromatic nitro compound by reaction with a finely divided metal and an acid, which comprises condensing the vapors of the aromatic nitro body which are evolved, collecting said condensate to form a liquid seal, passing finely divided metal through said liquid seal thereby mixing said material with said liquid, introducing the finely divided metal into the reduction mass, and introducing said liquid into the reduction mass.

8. The process of reducing an aromatic 1 nitro compound by reaction with a finely divided metal and an acid which comprises condensing to a liquid the vapors of the aro matic nitro body which are evolved, collecting said liquid to form a liquid seal, passing finely divided metal through said liquid seal thereby wetting said metal, and introducing the wetted metal into the reduction mass.

9. The process of reducing an aromatic nitro compound by reaction with finely divided iron and an acid, which comprises condensing the vapors of the aromatic nitro body which are evolved, collecting said condensate to form a liquid seal, passing finely divided iron through said liquid seal thereby wetting said iron, and reacting said wetted iron with an acid to reduce the nitro compound.

In testimony whereof we ailix our signatures.

JUSTIN F. WAIT. CROSBY FIELD. 

